Question

   Which of the three types of ELISA (Sandwich, Indirect, Competitive) would you use for the following situations? Explain your reasoning in each case.

a.     Determining if a person has an inflammatory disease that is characterized by high levels of the cytokine IL -6 in the blood.

    Sandwich ELISA because we can detect the presence of cytokine IL-6, and if it is present then we can determine the inflammatory disease as a differential diagnosis if IL-6 is high enough.

b. Determining if a person has sufficient IgG in their blood to protect against Covid-19.

c. Determining if an environmental sample contains dinitrophenol (a hapten)

Answer 1

Determining if a person has an inflammatory disease that is characterized by high levels of the cytokine IL -6 in the blood.

Yes, you are right. You can use a sandwich ELISA where we will use an antibody that catchIL-6 and another that will recognize it but labelled with an enzyme.

Determining if a person has sufficient IgG in their blood to protect against Covid-19.

For this we can use an indirect ELISA, where a COViD-19 antigen is positioned in the plate and then the blood sample of the patient is added into the plate. After that, we will use a labelled antibody that recognize the patient’s antibody.

Determining if an environmental sample contains dinitrophenol (a hapten)

For this, we can use a sandwich ELISA where the plate will contain an antibody that recognize the hapten. If the hapten is present, it will bind to the antibody. After that, we will add a second antibody which recognize the hapten but it is labelled with a reactive enzyme